<?php

namespace App\Common\Utill;

use App\Common\RedisCache\SsoLoginCache;
use App\Common\RedisCache\JwtTokenStringCache;
use App\Common\RedisCache\UserJwtTokenHashCache;
use Illuminate\Support\Facades\Log;

class Jwt
{
    //头部
    private static $header = array(
        'alg' => 'HS256', //生成signature的算法
        'typ' => 'JWT'  //类型
    );
    //使用HMAC生成信息摘要时所使用的密钥
    private static $key = 'KEY';

    /**
     * 获取jwt token
     * @param array $payload jwt载荷  格式如下非必须
     * [
     * 'iss'=>'jwt_admin', //该JWT的签发者
     * 'iat'=>time(), //签发时间
     * 'exp'=>time()+7200, //过期时间
     * 'nbf'=>time()+60, //该时间之前不接收处理该Token
     * 'sub'=>'www.admin.com', //面向的用户
     * 'jti'=>md5(uniqid('JWT').time()) //该Token唯一标识
     * ]
     * @return bool|string
     */
    public static function getToken(array $payload)
    {
        $deviceId = request()->header('deviceid', '');
        $gqTime = 86400 * 180;
        $arr = [
            'iss' => 'jwt_mcn', //该JWT的签发者
            'iat' => time(), //签发时间
            'exp' => time() + $gqTime, //过期时间
            'nbf' => time(), //该时间之前不接收处理该Token
            'sub' => '', //面向的用户
            'jti' => md5(uniqid('JWT') . time()), //该Token唯一标识,
            'deviceId' => $deviceId
        ];
        if ($deviceId) {
            //唯一的设备id存入redis
            $userSsoCache = new SsoLoginCache();
            $key = $payload['account'];
            $userSsoCache->setKeyParameter(['prefix' => $key]);
            $cacheData['account'] = $payload['account'];
            $cacheData['deviceId'] = $deviceId;
            $cacheData['id'] = $payload['id'];
            $userSsoCache->setEx(json_encode($cacheData), $gqTime);
        }

        $payload = array_merge($arr, $payload);
        if (is_array($payload)) {
            $base64header = self::base64UrlEncode(json_encode(self::$header, JSON_UNESCAPED_UNICODE));
            $base64payload = self::base64UrlEncode(json_encode($payload, JSON_UNESCAPED_UNICODE));
            $token = $base64header . '.' . $base64payload . '.' . self::signature($base64header . '.' . $base64payload, self::$key, self::$header['alg']);

            //token加入redis
            /*$UserJwtTokenCache = new UserJwtTokenHashCache();
            $UserJwtTokenCache->setKeyParameter();
            $UserJwtTokenCache->setFieldParameter(['unique' => $payload['account']]);
            $UserJwtTokenCache->set($token);*/

            // 使用新类型存储
            $jwtTokenCache = new JwtTokenStringCache();
            $jwtTokenCache->setKeyParameter([$payload['account']]);
            $jwtTokenCache->setEx($token, $gqTime);
            return $token;
        } else {
            return false;
        }
    }

    /**
     * 验证token是否有效,默认验证exp,nbf,iat时间
     * @param string $Token 需要验证的token
     * @return bool|string
     */
    public static function verifyToken(string $Token)
    {
        $tokens = explode('.', $Token);
        if (count($tokens) != 3)
            return false;

        list($base64header, $base64payload, $sign) = $tokens;

        //获取jwt算法
        $base64decodeheader = json_decode(self::base64UrlDecode($base64header), JSON_OBJECT_AS_ARRAY);
        if (empty($base64decodeheader['alg']))
            return false;

        //签名验证
        if (self::signature($base64header . '.' . $base64payload, self::$key, $base64decodeheader['alg']) !== $sign)
            return false;

        $payload = json_decode(self::base64UrlDecode($base64payload), JSON_OBJECT_AS_ARRAY);

        $jwtTokeCache = new JwtTokenStringCache();
        $jwtTokeCache->setKeyParameter([$payload['account']]);
        if ($jwtTokeCache->exists() == false) {
            //token不存在重新登陆
            $UserJwtTokenCache = new UserJwtTokenHashCache();
            $UserJwtTokenCache->setKeyParameter();
            $UserJwtTokenCache->setFieldParameter(['unique' => $payload['account']]);
            $is_token = $UserJwtTokenCache->fieldExists('',$payload['account']);
            if(!$is_token){
                Log::info('10002'."token不存在");
                return false;
            }
            // 更换新存储类型
            $exp = $payload['exp'] - time();
            if ($exp > 3) {
                $jwtTokeCache->setEx($Token, $exp);
            }
            // 移除旧的存储
            $UserJwtTokenCache->hDel();
        }

        //唯一的设备号
        if (isset($payload['deviceId']) && $payload['deviceId']) {
            $userSsoCache = new SsoLoginCache();
            $key = $payload['account'];
            $userSsoCache->setKeyParameter(['prefix' => $key]);
            //是否存在
            $userKey = $userSsoCache->exists();
            if ($userKey) {
                $ssoCacheData = $userSsoCache->get();
                if($ssoCacheData['deviceId'] != $payload['deviceId']){
                    Log::info('10002'."更换设备");
                    return false;
                }
            }else{
                Log::info('10002'."设备不存在");
                return false;
            }
        }

        //签发时间大于当前服务器时间验证失败
        if (isset($payload['iat']) && $payload['iat'] > time())
            return false;

        //过期时间小宇当前服务器时间验证失败
        if (isset($payload['exp']) && $payload['exp'] < time())
            return false;

        //该nbf时间之前不接收处理该Token
        if (isset($payload['nbf']) && $payload['nbf'] > time())
            return false;

        return $payload;
    }

    /**
     * base64UrlEncode  https://jwt.io/ 中base64UrlEncode编码实现
     * @param string $input 需要编码的字符串
     * @return string
     */
    private static function base64UrlEncode(string $input)
    {
        return str_replace('=', '', strtr(base64_encode($input), '+/', '-_'));
    }

    /**
     * base64UrlEncode https://jwt.io/ 中base64UrlEncode解码实现
     * @param string $input 需要解码的字符串
     * @return bool|string
     */
    private static function base64UrlDecode(string $input)
    {
        $remainder = strlen($input) % 4;
        if ($remainder) {
            $addlen = 4 - $remainder;
            $input .= str_repeat('=', $addlen);
        }
        return base64_decode(strtr($input, '-_', '+/'));
    }

    /**
     * HMACSHA256签名  https://jwt.io/ 中HMACSHA256签名实现
     * @param string $input 为base64UrlEncode(header).".".base64UrlEncode(payload)
     * @param string $key
     * @param string $alg 算法方式
     * @return mixed
     */
    private static function signature(string $input, string $key, string $alg = 'HS256')
    {
        $alg_config = array(
            'HS256' => 'sha256'
        );
        return self::base64UrlEncode(hash_hmac($alg_config[$alg], $input, $key, true));
    }
}
